Participant factors associated with psychosocial impacts of lung cancer screening: A systematic review

Abstract Background Psychosocial impacts of lung cancer screening (LCS) can cause both harm to individuals and serve as barriers to screening participation and adherence. Early data suggest that the psychosocial impacts of LCS are moderated by certain factors (e.g. sociodemographic characteristics and beliefs), but evidence synthesis is lacking. This systematic review aimed to understand individual‐level risk factors for psychosocial burden during LCS as a precursor to developing strategies to identify and support participants, and improve LCS engagement. Methods Four databases were searched for full‐text articles published in English reporting any association between participant factors and psychosocial outcomes experienced during LCS. Study quality was assessed by two independent investigators; findings were synthesised narratively. The review was pre‐registered with PROSPERO and adhered to PRISMA guidelines. Results Thirty‐five articles were included; most (33/35) studies were assessed at high or moderate risk of bias. Study designs were pre‐post (n = 13), cross‐sectional (n = 13), qualitative (n = 8) and mixed‐methods (n = 1) and conducted primarily in the United States (n = 17). Psychological burden in LCS varied, and was often associated with younger age, female gender, current smoking status or increased smoking history, lower education, lower socio‐economic group, not being married or co‐habiting and experience with cancer. However, results were mixed, and non‐significant associations were also reported across all factors. Beliefs (e.g. fatalism, stigma and expectation of LDCT results) and comorbid psychological burden were also linked to psychosocial outcomes, but evidence was sparse. Associations between risk perception, other participant factors and other psychosocial outcomes was inconclusive, likely reflecting individual biases in risk conceptualisation. Conclusion(s) Several participant factors are consistently reported to be associated with psychosocial impacts of LCS, though study heterogeneity and high risk of bias necessitate more robust evaluation. Further research on how perceptions, beliefs and expectations can be used to improve psychosocial outcomes during LCS is needed.


| INTRODUCTION
Globally, lung cancer is the leading cause of cancer mortality. 1This is generally attributed to advanced-stage diagnoses, making earlier detection of lung cancer a worldwide priority for cancer control.Low-dose computed tomography (LDCT) screening for lung cancer, evaluated in landmark trials in the United States and Europe, can achieve a 20%-24% reduction in lung cancer mortality in high-risk populations. 2,3There is, however, concern that lung cancer screening (LCS) can induce psychological harm.Some psychological burden for participants is seen across most cancer screening programmes, primarily presenting as anxiety or distress to the individual or their family/carers, with consequences for screening participation, adherence and other medical help-seeking behaviours as well. 4,5or LCS, there are additional unique considerations for psychosocial outcomes.These include the potential for shame, regret or stigma around smoking behaviour, high chance of finding indeterminate nodules requiring surveillance and potential for overdiagnosis. 6,7urrent consensus is that LCS is unlikely to result in any clinically significant psychological burden for participants, and if it does, adverse effects will not persist long term. 4,8owever, evidence from real-world LCS programmes is sparse, and most trial samples significantly under-represent priority groups. 4,8For example, participants in the Danish Lung Cancer Screening Trial were identified as likely being more 'psychologically robust' than a LCS population in a real-world setting. 9Measuring psychosocial outcomes in communities where LCS would take place is particularly important for socially driven factors and outcomes (e.g.risk perception, stigma and peer pressure as motivation to quit smoking), 10 given the difference in social processes and engagement between controlled trials and real-world practice.Additionally, enrolment in an organised LCS programme would entail ongoing surveillance and/or regular screening, and so there may be changing or compounding psychosocial impacts over time.Measurement across these routine and follow-up scans is limited as yet, and some study authors have acknowledged that long-term psychosocial impacts may have been overlooked. 5,9n addition to these considerations, evidence suggests that certain participant-level risk factors significantly mediate or moderate psychosocial burden during LCS. 4,5,11hese include sociodemographic characteristics, smoking status and history, and health beliefs, but a robust synthesis of the literature is needed.The aim of this systematic review is therefore to synthesise the evidence for individual factors associated with psychosocial outcomes of LCS.This would inform development of strategies for identifying and supporting participants who experience psychosocial harm through the LCS pathway.Additionally, psychological barriers to uptake have been connected to low rates of LCS, [12][13][14] so a better understanding of related risk factors could support improved participation and adherence.

| Search strategy
Databases searched were Medline, Embase, PsycINFO and Cumulative Index of Nursing and Allied Health Literature (CINAHL) from inception to 15 June 2022.An update of the search was performed on 12 July 2023.In consultation with a research librarian, a search strategy for Medline was developed then modified to suit the required syntax for other databases (Table S1).No search limitations for date, language or geography were used.Searches of references and cited articles for all included studies were also conducted.

| Study inclusion and exclusion criteria
Studies were included if they were original, full-text articles reporting quantitative or qualitative psychosocial burden were also linked to psychosocial outcomes, but evidence was sparse.
Associations between risk perception, other participant factors and other psychosocial outcomes was inconclusive, likely reflecting individual biases in risk conceptualisation.

Conclusion(s):
Several participant factors are consistently reported to be associated with psychosocial impacts of LCS, though study heterogeneity and high risk of bias necessitate more robust evaluation.Further research on how perceptions, beliefs and expectations can be used to improve psychosocial outcomes during LCS is needed.
outcomes.Studies were excluded if they were reviews, case studies, case reports, opinions, comments or editorials.Participants in LCS via LDCT across the entire screening continuum (including enrolment, recruitment and follow-up) were included; though studies where participants were only eligible for LCS (and had not engaged in the LCS pathway) were not.
Included factors and outcomes are presented in Box 1.Any psychosocial outcome was considered, including those related to decision-making and smoking cessation (e.g.motivation and readiness to quit), though behavioural smoking outcomes (e.g.quit rates) were excluded.Only experienced outcomes were included, thus studies which reported on anticipated impacts of LCS were excluded.Relevant factors were any participant-level predictor, moderator, mediator or covariate of an outcome of interest.Broadly, these were categorised into sociodemographic factors (e.g.age, gender and education level), health-related factors (e.g.smoking history, experience with cancer and pre-existing psychological burden), beliefs (e.g.risk perception, fatalism and stigma) and other factors.Stigma was included as a belief outcome, though noting that it has social aspects as well.There was cross-over between factors and outcomes, with some categorised as both (e.g.certain beliefs).
All relevant analyses within each study were reported; some studies examined multiple outcomes under a single category (e.g.anxiety and HRQoL under psychological outcomes), therefore results from a single study were sometimes conflicting within category summaries.Where a factor of interest was examined as a modifier or covariate, studies were included if the relationship between the factor of interest and the outcome was directly reported.

| Data extraction and synthesis
Procedures for data synthesis and analysis were determined a priori.The lead investigator (KM) undertook title, abstract and full-text screening, with a second investigator (BN or AS) independently assessing a 20%

Factors Outcomes
Sociodemographic factors

Social
• Seeking social support subset at both stages of screening to ensure agreement and consistency.Any discrepancies were discussed with reference to the pre-defined inclusion and exclusion criteria, with consultation by a third investigator if required.Data extraction of study characteristics was performed by the lead investigator (KM) and checked for accuracy by another investigator (TL or CJJ).Results were extracted independently by two investigators (KM and either TL or CJJ).Evidence was summarised by factor and outcome of interest; given the heterogeneity across studies, meta-analysis and subgroup analysis were not considered appropriate and instead results were synthesised narratively.

| Quality assessment
Quality assessment was performed by two investigators independently (KM and either TL or CJJ), with any discrepancies resolved via discussion or via an additional investigator (BN).Validated tools from the Joanna Briggs Institute (JBI) were used and an overall assessment (low, moderate or high risk of bias) was given based on pre-determined criteria about the number of appraisal checklist items fulfilled. 15Studies were not excluded from the review based on methodological quality, but this was considered in the interpretation of findings.

| Protocol and registration
This systematic review presents the participant factors associated with psychosocial outcomes of LCS as part of a larger review (PROSPERO registration: CRD42022334634).A companion systematic review will report on the programme factors (service delivery aspects and interventions).Risk of bias was assessed as high (n = 16), moderate (n = 17) and low (n = 2).Quality ratings for quantitative studies included in this review were commonly hindered by possible selection bias and coverage bias, and sample sizes were also often small and/or unjustified.Quasiexperimental study designs frequently lacked control groups, and cross-sectional designs had low response rates.Full quality appraisals according to the JBI critical appraisal tool checklists are provided in Tables S3-S5.

| Study characteristics
A summary of the factor-outcome combinations examined is provided in Table S2.Key results for each factoroutcome combination are summarised in Table 2 and are presented narratively below by broad outcome categories: psychological outcomes (both general and lung cancer or LCS-specific; e.g.anxiety and lung cancer-specific worry), beliefs (e.g.risk perception and fatalism), decision-related (e.g.decisional conflict), and smoking-related (e.g.motivation to quit smoking).
2][23][24][25]27,39 Similarly, higher pack years and a more pronounced smoking history were linked to increased psychological burden in some cases (n = 6), 18,22,28,36,40,42 but not others (n = 3).18,22,25 Personal or family experience with cancer (including lung cancer) was significantly associated with worse psychological outcomes in half of the studies which examined the factor (n = 3).20,23,40 Five studies reported the impact of pre-existing or comorbid psychological burden, all of which indicated an association with psychological harm during LCS. 20,22,25,26,42 On study also suggested that for those with low distress at baseline, LDCT participants had higher distress than nonparticipants after receiving results.20 Findings on the impact of risk perception on psychological outcomes were mixed and appear to be individualised (n = 4).22,29,42,44 Expectation of LDCT results impacted subsequent psychological outcomes differently across three studies.23,42,47 One study suggested preparation for an 'indeterminate' or 'abnormal' LDCT result could reduce psychological burden, 42 but this had no reported effect in another study.23 Those who received an expected 'normal' result reported the lowest concern in one study; 23 another described that if a 'normal' result was unexpected then this also led to relief and reduced stress.47 The impact of perceived stigma and fatalistic health beliefs were examined in one qualitative study; while higher fatalism led to positive psychological outcomes after receiving results (relief and reassurance), smoking-related stigma appeared to have the opposite effect. 42 One study repoed that making an informed decision to participate in LCS had no impact on psychological outcomes, including after receiving an indeterminate result.50 Two qualitative studies examined social factors, with one suggesting that social support provided a 'buffer' of emotional support throughout the LCS pathway, 42 and the other describing feelings of guilt and shame in having to inform family members (possibly driven by internalised blame or stigma around smoking).  Risk peeption was measured as an outcome in nine studies.Higher perceived lung cancer risk was associated with younger age 21,29,30 and female gender 21,22,30 in three studies each, though no relationship was reported in three 19,22,31 and four 19,22,29,31 studies, respectively.No association was reported between risk perception and race or ethnicity 19,21,38 (n = 3), income or deprivation level 21,39 (n = 2) or relationship status 19,21 (n = 2).Most studies reported no relationship with education level 22,39 (n = 2) as well, though one study reported those with higher education having lower risk perception.19 Family history of lung cancer was associated with comparative risk perception (risk compared to others) in two studies, 22,30 but not absolute risk perception in one study.22 Previous cancer was also not associated with risk perception in two studies.22,30 The association between smoking status and risk perception varied, reported as worse for those currently smoking (n = 4), 19,21,22,39 those T A B L E 1 (Continued) who had quit smoking (n = 1) 30 and not significantly different (n = 2). 22,29 Hiher number of pack years was associated with higher perceived risk in one study, 30 but not in two others.22,29 Two studies reported a significant relationship between increased risk perception and worse psychological outcomes (anxiety, depression and HRQoL), 22,30 but not lung cancer worry.22 Calculated lung cancer risk via PLCO m2012 was not associated with risk perception in two studies, 22,31 but was in another.30 One study examined the impact of informed decision-making on risk perception, finding that those with an informed decision had more accurate cognitive perceptions of risk, though there was no relationship with perceived affective (feelings about) this risk.50 3.3.2 | Fatalism andperceptions of control Three studies measured health beliefs related to fatalism and perceptions of control.Higher fatalism was linked to not being in a relationship or co-habiting (n = 1), 21 being of African American (n = 1) 38 or Asian (n = 1) 21 ethnic backgrounds, and current smoking status (n = 1).21 One highquality cross-sectional study specifically measured other health beliefs, finding that more negative perceptions of personal control were associated with female gender, less affluence, current smoking status and Asian ethnicity. 21he same study found that participants with Black and Asian ethnic backgrounds had more positive perceptions of the efficacy of lung cancer treatment, as did men, those who were older, and those who were married, co-habiting or in a partnership.21 Differences in perceptions of stigma were described in one qualitative study as moderating fatalistic outlooks.42

| Stigma
Four studies examined stigma, with two reporting that perceived stigma was more pronounced for women. 21,37ounger age and White ethnicity were also associated with higher perceived stigma in one study. 21Stigma related to current smoking status was described in two qualitative studies. 40,42Further, significantly higher perceived stigma was reported by people who were currently smoking in another quantitative study. 21

| Decision-related psychosocial outcomes
Three studies measured decision-related psychosocial outcomes.Most reported no significant difference in outcomes for age (n = 2), 32,33 level of education (n = 2), 32,33 employment status (n = 1) 32 or gender (n = 2). 32,33eople who had quit smoking were more likely to report worse decisional outcomes compared with people who were currently smoking in two studies, 27,33 though a significant relationship was only reported in one. 33hite 32,33 (n = 2) and Hispanic 33 (n = 1) participants were reported as being less likely to experience decisional conflict about LCS than other ethnicities.One study reported that the number of times screened for lung cancer, or time since last scan, was not related to decisional outcomes. 32

• Expectation of results
Relief Interviews High

| Smoking-related psychosocial outcomes
Smoking-related psychosocial outcomes were assessed in 14 studies.Most analyses reported no significant relationship between smoking-related outcomes and age (n = 3), 31,34,35 gender (n = 4) 21,31,34,35 or race/ethnicity (n = 3), 21,34,35 except women being more likely to endorse concerns about weight gain after quitting and African American participants being less likely to endorse concerns about nicotine withdrawal symptoms in one study. 34urrent smoking status was associated with more smoking worry 43 (n = 1) and a higher intention to quit 43 (n = 1), but lower confidence in quitting 43 (n = 1) and lower perceived efficacy of smoking cessation 21 (n = 1), in conjunction with LCS.There was no difference in motivation to quit by pack years in two studies. 28,35orry or concern about lung cancer was associated with readiness or motivation to quit smoking in five studies, 30,35,42,45,51 though with varying impacts.For some participants, psychological harm experienced during LCS appeared to motivate quitting smoking, 30,35,45 while it had no (or the opposite) effect for others. 42,44,45Two studies reported that those with higher perceived risk showed more motivation or intention to quit smoking (n = 2), 30,46 though one study suggested the inverse 35 and another two studies suggested no relationship between risk perception and motivation to quit. 35,44Two qualitative studies described the COVID-19 pandemic as creating additional stress and anxiety that reduced motivation or readiness to quit smoking; 45,49 this was reported as both specific to smoking cessation interventions during LCS 45 and more generally. 49

| Social outcomes
Social outcomes were only described in one qualitative study, which reported that a fatalistic outlook reduced seeking of social support. 42

| DISCUSSION
This review found that several participant factors were consistently reported to be associated with psychosocial outcomes in LCS.However, associations were not consistent across studies and non-significant findings also frequently reported.This may be due to bias in study designs and lack of power to show associations; indeed, small and/or unjustified sample sizes were an issue across many quantitative studies in risk of bias assessment.Many of the factors and outcomes examined were also interrelated, which should be considered in interpretation of findings.Sociodemographic and smoking-related characteristics were the most frequently examined factors.Correlations between younger age, female gender, and current smoking status, and increased psychological burden were commonly reported.Similar findings were reported recently in the Watch the Spot trial (which included those with both screening and incidentally detected nodules). 52Links with pre-existing or comorbid psychological harm, expectation of LDCT results and other beliefs were also found, though were examined in fewer studies and were more nuanced.While this reviews' results are limited by study quality (as systematically assessed in our work), they provide a basis for understanding who may be at risk of psychological harm during LCS based on all available evidence.These T A B L E 2 Summary of key results.
Beliefs (n = 8) Some analyses (n = 3) reported women to have higher perceived risk of lung cancer; 21,22,30 while others (n = 4) reported no difference by gender. 19,22,29,31In a high-quality cross-sectional study, women were reported to have less feelings of personal and treatment control. 21Two studies (one qualitative and one quantitative) each reported stigma was more common in women. 21,37Women rated the perceived efficacy of LCS as significantly more important for making a LCS decision in one study. 27cision-related (n = 3) Associations between gender and decisional outcomes was measured in three studies. 27,32,33wo studies found no difference in decisional conflict by gender, 32,33 one study reported women having significantly lower decisional regret than men. 27oking-related (n = 4) Studies mostly reported no significant association between gender-and smoking-related psychosocial outcomes (n = 4), 21,31,34,35 except women being more likely to endorse concerns about weight gain after quitting in one study. 34ce/ ethnicity (n = 9) Four studies reported no differences in psychological outcomes across race or ethnicity, 17,19,20,38 primarily for lung cancer or LDCT distress or fear.Two others reported worse outcomes for participants with African American 38 (n = 1) or Asian 21 (n = 1) ethnic backgrounds.
Beliefs (n = 3) Three studies measured risk perception and found no significant relationship with race. 19,21,38igher fatalism and more negative perceptions of personal control were reported for participants with African American 38 or Asian 21 ethnic backgrounds in one study each.Though in one study, both participants with Black and Asian ethnic backgrounds had significantly more positive perceptions of the consequences of lung cancer and perceptions of treatment control, while White participants reported higher perceived stigma. 21cision-related (n = 2) Across two studies, White 32,33 (n = 2) and Hispanic 33 (n = 1) participants were significantly less likely to experience decisional conflict about LCS than other ethnicities.

Smoking-related (n = 3)
There was no significant relationship between race/ethnicity and motivation to quit smoking 31,34,35 (n = 2), readiness to quit smoking 35 (n = 1) or perceived efficacy of smoking cessation 21 (n = 1).In one study, those who identified as non-Hispanic Black had significantly more concerns about withdrawal symptoms and were more likely to believe that they do not need to make smoking changes. 34actor (# of studies)

Education
Higher levels of education were associated with better psychological outcomes in four studies, [17][18][19]22 including for cancer-related distress or fear 18,19,22 (n = 3) and anxiety 18,19 (n = 2).However, analyses in another four studies 17,20,22,39 reported no relationship, specifically with cancer distress, fear, worry or impact on mood (n = 4) 17,20,22,39 and anxiety (n = 4).17,22,39 Results from the K-LUCAS trial was the only study to show minimally higher anxiety in those with higher education levels, though this study had a high risk of bias and significance between groups was not calculated. 28 Belies (n = 5) The association between risk perception and education was varied, with two studies reporting no relationship, 22,39 and one study reporting participants with higher education having lower perception of lung cancer risk. 19Higher objective numeracy scores, but not subjective numeracy or education level, were associated with the importance of perceived efficacy of LCS for making LCS decisions in one study. 27cision-related (n = 2) Two studies found no significant relationship between education level and decisional conflict about LCS. 32,33oking-related (n = 1) The K-LUCAS trial reported higher motivation to quit smoking in the higher education group, however between-group analysis was not completed. 28come, employment, insurance and deprivation (n = 9) Seven studies examined the relationship between income, insurance, deprivation, and employment status with psychological outcomes.Five studies 17,20,23,26,28 found worse psychological outcomes for those who had higher levels of deprivation, lower income or were unemployed; however, relationships in two of these studies were no longer significant after multivariate analysis. 17,20In addition, three studies 17,21,39 reported no significant association between psychological outcomes, with one of these being the only high-quality (low risk of bias) quantitative study included. 21liefs (n = 3) Two studies found no significant relationship between income or deprivation level, and risk perception. 21,39One high quality study reported that greater affluence was significantly associated with more negative perceptions of consequences and higher perceived stigma, but more positive perceptions of personal control. 21There was no association between fatalism and perception of treatment control. 21There was no significant association between insurance and the importance of perceived efficacy of LCS for making a LCS decision in one study. 27cision-related (n = 1) One study examined decisional conflict and employment, finding no significant association. 32oking-related (n = 2) Greater affluence was significantly associated with lower perceived efficacy of smoking cessation in a high-quality cross-sectional study. 21The K-LUCAS trial reported slightly higher motivation to quit smoking for those with lower income; however, between-group analysis was not completed. 28lationship status (n = 6) Married or co-habiting participants were reported to have significantly better psychological outcomes in four studies, 17,19,20,26 however analyses across another four studies reported no association between relationship status and psychological burden, 17,19,21,23 with one of these being the only high-quality (low risk of bias) quantitative study included. 21liefs (n = 2) Two studies reported no significant relationship between relationship or marital status and risk perception. 19,21In one high quality cross-sectional study, those who were in a partnership or co-habiting had more positive perceptions of treatment control and fatalism, but there was no relationship with the consequences of lung cancer, perceptions of personal control or stigma. 21oking-related (n = 1) One study found no significant relationship between perceived efficacy of smoking cessation and relationship status. 21alth-related factors Health status (n = 5) Alcohol consumption 25 and Body Mass Index (BMI) 22 were not significantly associated with psychological outcomes across one study each.In another study, a participant's number of comorbidities was reportedly associated with antidepressive or anxiolytic use. 26liefs (n = 3) Having asthma, 30 COPD 30 and symptoms (such as dyspnoea or cough), 30 but not BMI 22 or the number of comorbidities, 30 were associated with lung cancer risk perception in one study each.Medical conditions were unrelated to the importance of perceived efficacy of LCS for making LCS decisions in one study.Personal or family experience with cancer (including lung cancer) was associated with higher lung cancer distress, concern about LDCT result or fear in three studies, 20,23,40 but had no links to psychological burden in three other studies. 22,24,25liefs (n = 2) Family history of lung cancer was associated with comparative risk perception in two studies, 22,30 but not absolute risk perception in one. 22Previous cancer was not associated with risk perception in two studies. 22,30One study reported an associated between the number of previous chest radiographs, but not CT scans, with risk perception. 30cision-related (n = 1) The number of times someone was previously screened for lung cancer, or the time since previous scan, were not related to decisional outcomes in one study. 33oking-related (n = 1) In one study, those attending for a baseline scan (rather than an annual follow-up scan) reported higher readiness and motivation to quit smoking. 35oking status and history (n = 21) Most analyses (n = 9) reported no significant association between smoking status (i.e.current versus former smoking) and outcomes such as anxiety 17,18,22,25,39 (n = 5) and lung cancer-specific fear, worry or concern (n = 4). 17,21,23,27Seven studies reported worse psychological outcomes for participants who reported current smoking, [18][19][20]22,36,39,41 though these was not always clinically important. Four studie reported that more pack years were associated with increased psychological burden, 18,22,28,36 but three studies also reported no significant relationship.18,22,25 In two qualitative studies, more pronounced smoking history was often linked to increased worry, guilt and shame in the context of LCS.40,42 Beliefs (n = 10) The relationship between smoking status and risk perception was varied, reported as worse for people currently smoking (n = 4), 19,21,22,39 worse for people who had quit smoking (n = 1), 30 and not significantly different (n = 2). 22,29Higher number of pack years was associated with higher perceived risk in one study, 30 but not in two others. 22,30Younger smoking start age and higher average cigarettes smoked per day were also associated with higher risk perception in one study. 30tigma was described by people currently smoking in two qualitative studies, 40,42 with significantly higher perceived stigma reported by this group in another quantitative study. 21Higher fatalism and reduced perceptions of control were also higher in those who were currently smoking. 21Two studies indicated no difference in perceived efficacy or accuracy of LCS by smoking status. 27,41cision-related (n = 2) People who formerly smoked were more likely to report worse decisional outcomes compared with those currently smoking in two studies, 27,33 though a significant relationship was only reported in one. 33Pack years was not significantly associated with decisional conflict in one study. 33oking-related (n = 5) Findings on the impact of smoking status on smoking-related psychosocial outcomes were mixed.Current smoking status was associated with more smoking worry 43 (n = 1) and a higher intention to quit 43 (n = 1), but lower confidence in quitting 43 (n = 1) and lower perceived efficacy of smoking cessation 21 (n = 1), in conjunction with LCS.Another study reported that participants with greater nicotine dependence were significantly more likely to endorse concerns about quitting smoking. 34There was no difference in motivation to quit by pack years in two studies, 28,35 though readiness and motivation to quit was associated with being less likely to smoke every day and having made a 24-hour quit attempt in the last 7 days in one study. 35e-or co-existing psychological burden (n = 9) Psychological (n = 5) One study reported that for those with low distress at baseline, LDCT participants (versus non-participants) had significantly higher distress 2 weeks post-results. 20However, for those with initial high distress, completing LDCT was not impactful, and overall distress remained high. 20Pre-existing concern about lung cancer was associated with anxiety about LCS (and consequential relief following LDCT results) in one qualitative study. 42Three studies indicated that pre-existing levels of anxiety and depression were associated with worse harm in other psychological outcomes at different points during LCS. 22,25,26liefs (n = 2) Two studies reported a significant relationship between worse psychological outcomes (anxiety, depression and HRQoL) and higher absolute and comparative risk perception. 22,30However, one study also reported no association between lung cancer worry and risk perception. 22oking-related (n = 5) Worry or concern about lung cancer was significantly associated with readiness or motivation to quit smoking in two quantitative studies. 30,35This relationship was qualitatively described in three studies; 42,44,45 though, the reported association was more varied.Psychological harm experienced during LCS appeared to motivate quitting smoking for some participants, while it had no effect for others 42,44,45 T A B L E 2 (Continued)  findings are also useful when considering psychological barriers to LCS uptake and developing campaigns or strategies to engage certain groups. 5onsidering the evidence for risk factors associated with psychological harm found in this review, interventions to manage psychosocial experiences during LCS should not be 'one size fits all'.Different assessment, referral and intervention pathways which target specific factors or at-risk groups should be considered in LCS programme design.For example, people who live alone or do not have support systems could be assessed and referred to an intervention focused at providing social support, which have been shown to improve quality of life for lung cancer patients. 53Acknowledging that most participants in LCS do not experience clinically significant psychological burden, avoiding a blanket universal intervention approach may also have cost-effectiveness benefits, 54,55 especially considering participation volumes in larger screening programmes.
A key factor identified in our review was pre-existing or comorbid psychological burden, which appears to significantly predict other psychological outcomes during LCS.Measuring participants' anxiety or distress at baseline participation in a LCS programme could therefore be critical in identifying participants who may experience psychological harm.For those with a cancer diagnosis, distress screening is part of the standard of care and there is a myriad of practice guidelines, 56 though none extend to cancer screening.While measuring distress at every LCS visit may not be feasible or useful with the number of participants in a screening programme, strategies to enable participants to easily communicate distress, and for providers to easily identify it, at every touchpoint could be considered.As providers are often time-poor during shared decision-making discussions, 57 approaches to assess participant distress without adding to clinician time burden may be useful.Pre-completion of patient-reported outcome or experience measures, or assessment of psychological outcomes by a nurse prior could be beneficial.Programme coordinators or 'navigators' have also been successful in providing engagement and support for participants during LCS, so involving them in distress screening and management could also be an option. 58,59Appropriate triage and referral pathways for those experiencing psychosocial harm are also needed, which would require programme-level set-up and resourcing. 56indings on factors and outcomes associated with risk perception in this review were varied.This likely reflects the complexity of risk comprehension and the integral role of personal, cultural and social biases.With this in mind, it is important to delineate between absolute (how likely are you to get lung cancer?) and comparative (how likely are you to get lung cancer compared to someone similar to you?) risk perception. 60Comparative risk perception has a direct social focus and therefore may be more tied up in cognitive biases and have other consequences for psychosocial outcomes. 61This difference was often not articulated in studies included in this review, with 'risk perception' used as an umbrella term for both concepts.Further research should investigate the differences in absolute and comparative risk perception on psychosocial outcomes specifically for LCS, especially considering the unique personal and social complexities around smoking behaviour and stigma in LCS.Findings from the Manchester Lung Health Check pilot suggest that provision of comparative (rather than absolute) risk could support better risk understanding, however it was flagged that further research was required to determine the optimal approach to risk communication in the LCS setting. 22The general population almost always significantly overestimate their cancer risk, and while evidence shows that risk information can help align perceptions closer to actual estimates, overestimations remain. 31,61In addition, there Factor (# of studies)

Outcome of interest Results
Informed decisionmaking and knowledge (n = 2) One study reported that participants who did not make an informed decision to participate in LCS experienced no worse anxiety, HRQoL or lung cancer specific distress than subjects who did make an informed decision (including after receiving an indeterminate result). 50liefs (n = 1) One study examined the impact of informed decision making on risk perception, finding that those with an informed decision had more accurate cognitive perceptions of risk, though there was no relationship with affective risk perception 50 Decision-related (n = 1) One study found a significant correlation between knowledge and decisional conflict. 32cial factors (n = 2) Two qualitative studies reported on social factors.One suggested that social support provided an important 'buffer' of emotional support throughout the screening pathway. 42Another suggested that having to disclose results to family members resulted in guilt and shame (possibly driven by internalised blame or stigma around smoking).  is evidence that people who have stopped smoking underestimate their lung cancer risk due to perceived protective health benefits of having quit. 62These enduring inaccurate conceptualisations of risk are possible drivers behind the nil or positive impacts of personalised cancer risk information (PCRI) seen for psychological outcomes in the broader literature. 61This further necessitates research on how to effectively communicate risk in LCS, and to understand the true psychosocial effects.4][65] Lung cancer stigma is especially pervasive owing to decades of public focus on its links with smoking, 63,66 and the narrative of smoking being an individual 'choice' rather than an addiction.Most work to date on stigma in lung cancer has focused on those with a diagnosis, with less evidence on the impact of stigma in earlier stages of the lung cancer continuum or as early as the LCS pathway.Recent qualitative studies suggest that stigma is present during LCS and that it can act as a barrier to participation in screening, 37,67,68 but there is limited evidence on the psychosocial consequences of stigma on screening, as identified by this review.Some studies referenced internalised shame, blame and guilt around smoking behaviour, 40,42 but there was little exploration of the impacts of interpersonal or societal level stigma. 63A detailed understanding of how and where stigma emerges during the LCS pathway is needed to design appropriate strategies to address it.

| Limitations
There are limitations to address in this review.Critically, the findings from this review are based on a heterogeneous group of studies with varying methodological quality, with risk of bias assessed as moderate or high in 33 of 35 included studies.There was variation in study design and measurement of factors and outcomes of interest.Most studies were completed in trial settings or at a single site, limiting generalisability of conclusions to real-world groups who would be participating in LCS.Selection bias and coverage bias were also common across quantitative studies.

| CONCLUSION
This review provides the first comprehensive synthesis of participant-level factors associated with psychological burden for LCS participants.These findings, despite the acknowledged limitations of the existing evidence, point to a clear association between certain individual factors and psychosocial impacts during LCS.Sociodemographic and health risk factors-for example, age, gender and smoking status-were the most examined in this review and are easily identifiable among participants in an LCS programme context.However, the evidence for these factors was mixed in terms of significant and non-significant relationships reported.Some factors-particularly beliefs and expectationswere examined less frequently, and these factors may require more time and effort to elucidate during LCS, but could serve as more refined predictors of psychological harm and warrant further research.Importantly, the interplay of different participant factors in the LCS context should be considered when designing strategies to manage psychosocial experiences.

T A B L E 1 Key characteristics of included studies. Author, year Location (trial/ programme) Study design Study aim Participant description, N
Intervention: N = 48 Usual care: N = 36 27